As a rule, all Child Benefit stops on the 31st of August on, or immediately after, the day a child celebrates their 16th birthday. An exception may apply if they stay in approved education or training.
You must notify the Child Benefit Office if your child chooses to stay in education or training. They will also need to know if at any time they leave that education or training.
Even so, you must report any of these changes in child circumstances to the Child Benefit Office and without delay if your child:
Begins paid work for 24 hours a week or more.
Will live away from you for either 8 weeks in a row or more than 56 days in a 16-week period.
Will go abroad permanently, for more than 12 weeks, or moves to or from Northern Ireland.
There is another reason to report changes to Child Benefit claims. It can increase the likelihood of paying the High Income Child Benefit Tax Charge. Your income (or your partner's earnings) may affect the charge if it goes over the threshold of £50,000.
Note: You must report circumstantial changes even if you choose to stop receiving Child Benefit.
How to Report Changes to Child Benefit in the United Kingdom